Complete the sentences with 'should' or 'shouldn't'.

1. You **shouldn't** be late for your classes. 2. You **shouldn't** argue with your parents. 3. You **should** be attentive to your friends' problems. 4. You **should** be honest with your friend. 5. You **shouldn't** eat too much. 6. You **should** inform your parents if you are getting late. 7. You **should** tell your friend about your problems. 8. You **shouldn't** mix with people who smoke. 9. You **shouldn't** cross the street here.